With this change it is possible to send file descriptors to PID 1, via
sd_pid_notify_with_fds() which PID 1 will store individually for each
service, and pass via the usual fd passing logic on next invocation.
This is useful for enable daemon reload schemes where daemons serialize
their state to /run, push their fds into PID 1 and terminate, restoring
their state on next start from the data in /run and passed in from PID
1.
The fds are kept by PID 1 as long as no POLLHUP or POLLERR is seen on
them, and the service they belong to are either not dead or failed, or
have a job queued.
When setting up a namespace, mount flags like noexec, nosuid and
nodev are cleared, so the mounts always have exec, suid and dev
flags enabled.
Copy source directory mount flags to target mount when remounting
the bind mounts.
Regression introduced by ed757c0cb0
Mirror the implementation of columns(), since the fd_columns()
functions returns a negative integer for errors.
Also fix columns() to return the unsigned variable instead of the
signed intermediary (they're the same, but better to be explicit).
Commit a2a5291b3f changed the parser to reject unfinished quoted
strings. Unfortunately it introduced an error where a trailing
backslash would case an infinite loop. Of course this must fixed, but
the question is what to to instead. Allowing trailing backslashes and
treating them as normal characters would be one option, but this seems
suboptimal. First, there would be inconsistency between handling of
quoting and of backslashes. Second, a trailing backslash is most
likely an error, at it seems better to point it out to the user than
to try to continue.
Updated rules:
ExecStart=/bin/echo \\ → OK, prints a backslash
ExecStart=/bin/echo \ → error
ExecStart=/bin/echo "x → error
ExecStart=/bin/echo "x"y → error
dup3() allows setting O_CLOEXEC which we are not interested in. However,
it also fails if called with the same fd as input and output, which is
something we don't want. Hence use dup2().
Also, we need to explicitly turn off O_CLOEXEC for the fds, in case the
input fd was O_CLOEXEC and < 3.
This works now:
# systemd-nspawn -xb -D / -M foobar
Which boots up an ephemeral container, based on the host's root file
system. Or in other words: you can now run the very same host OS you
booted your system with also in a container, on top of it, without
having it interfere. Great for testing whether the init system you are
hacking on still boots without reboot the system!
Also, rename filename_is_safe() to filename_is_valid(), since it
actually does a full validation for what the kernel will accept as file
name, it's not just a heuristic.
loop_write() didn't follow the usual systemd rules and returned status
partially in errno and required extensive checks from callers. Some of
the callers dealt with this properly, but many did not, treating
partial writes as successful. Simplify things by conforming to usual rules.
If /etc was read only at boot time with an empty /etc/machine-id, the latter
will be mounted as a tmpfs and get reset at each boot. If the system becomes rw
later, this functionality enables to commit in a race-free manner the
transient machine-id to disk.
If the format string contains %m, clearly errno must have a meaningful
value, so we might as well use log_*_errno to have ERRNO= logged.
Using:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\((".*%m.*")/log_\1_errno(errno, \2/'
Plus some whitespace, linewrap, and indent adjustments.
Using:
find . -name '*.[ch]' | while read f; do perl -i.mmm -e \
'local $/;
local $_=<>;
s/(if\s*\([^\n]+\))\s*{\n(\s*)(log_[a-z_]*_errno\(\s*([->a-zA-Z_]+)\s*,[^;]+);\s*return\s+\g4;\s+}/\1\n\2return \3;/msg;
print;'
$f
done
And a couple of manual whitespace fixups.
As a followup to 086891e5c1 "log: add an "error" parameter to all
low-level logging calls and intrdouce log_error_errno() as log calls
that take error numbers", use sed to convert the simple cases to use
the new macros:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\("(.*)%s"(.*), strerror\(-([a-zA-Z_]+)\)\);/log_\1_errno(-\4, "\2%m"\3);/'
Multi-line log_*() invocations are not covered.
And we also should add log_unit_*_errno().
